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THE TREATMENT OF MARINE METEſ)||||||ſ|{\| ||\|\, WITH SPECIAL REFERENCE
||| ||E WORK ()|| ||E UNITED STATES ||Y||{ſ}(|{\|| ||FFICE.
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NOTE BY THE LIY DEROGRAPHER,
This pamphlet treats of a question to the details of which the present Hydrographer has
devoted much personal attention during his term of office, now on the eve of conclusion. At the
outset it was hoped that greater progress than has been realized could be made in the time which
has elapsed, but it was soon seen that there was little reason for assuming that Congress could
grant an increased appropriation at the present time for prosecuting the meteorological work of the
Office. Convinced, therefore, of the necessity of fixing upon some system which could be utilized
with the means at hand, the method of treatment described herein was gradually developed as
promising great economy in arriving at final results. The Hydrographer has sought in the
present pamphlet to furnish a clear description of the method which his best judgment and mature
consideration have led him to adopt. The importance of giving the pamphlet a somewhat extended
circulation has been urged upon him by the growing impression, especially among foreign nations,
that the United States is no longer laboring with energy in that peculiar field in which for many
years it stood easily first. The Hydrographer is much indebted to Lieut. Chauncey Thomas,
U. S. N., formerly in charge of the Division of Marine Meteorology, and to Mr. James Page,
Meteorologist of that Division, for their active and sympathetic assistance. This pamphlet has
been prepared by Mr. Page. The office is indebted to Mr. Herman Hollerith for the loan of a
number of the blocks from which the illustrations are printed.
C. D. Sigsber,
Captain, U. S. Navy, Hydrographer.
HYDROGRAPHIC OFFICE,
Washington, D. C., April, 1897.


THE TREATMENT OF MARINE METEOROLOGICAL DATA, WITH
SPECIAL REFERENCE TO THE WORK () F THE UNITED STATES
HYDROGRAPHIC OFFICE,
The demands made of late years upon the United States Hydrographic Office for meteorolog-
ical information, and the vast store of meteorological observations of which the Office, by the zeal
of its voluntary observers, without regard to nationality, now finds itself in possession, have con-
stantly served to keep before the mind of the present Hydrographer the necessity of giving earnest
consideration to the question of the treatment to which this material should be subjected, in order
that the best results might be attained. The difficulties of the problem have been great. Com-
pelled to exercise a rigid economy, and to reckon only upon an inadequate force, it was evident at
the outset that the method devised must be of such a nature that it would involve a sensible increase
neither in the expense nor in the personnel of the Office. The question, furthermore, of what con-
stituted the highest utility of meteorological observations, and what original steps were necessary
in order that this degree of utility might be achieved, was in itself a difficult one to answer.
Circumstances have changed, since, as in Maury's time, the whole aim was to assemble over each
five-degree square of ocean surface a reasonable number of meteorological observations. The
abundance of the data at hand, the total inadequacy of the methods hitherto devised, these and
other subjects, each involving delay, had to be taken up in turn and considered, so that now, at
the close of his term, he finds that he has done little more than point the way toward the goal at
which he had hoped, ere this, to have arrived.
THE MATERIAL FOR DISCUSSION.
The meteorological material contained in the Office may be summarized as follows:
(a) An indefinite number of rough logs, presented to the Office by the masters of vessels.
(b) Three thousand eight hundred abstract logs, each one containing the three months'
meteorological record of the vessel to which issued.
(c) Eighty-five thousand Forms 105a (Greenwich Mean Noon Observations) and 105b (Abstract
Storm Logs).
Leaving out of consideration the first class, the material comprised under (b) consists of the
quarterly meteorological logs issued by the Office subsequent to 1878. This form of abstract log
called for a single observation per day of the vessel's position; for a record of the direction and
amount of the set during the preceding twenty-four hours; and for bi-hourly observations of the
direction and force of the wind, the height of the barometer, the temperature of the air and of
the surface water, the character of the weather, the form of clouds, the proportion of clear sky,
and the state of the sea.
The large majority of these books are very completely filled, owing to the plan adopted of
awarding the sailing charts allotted by the Office to its observers as a compensation for their
services, only to those observers attaining a grade of “excellent.” Barometer comparisons were
obtained whenever possible, and the general character of the observations is good. The total
number of complete sets of observations derivable from this source is in the neighborhood of

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6
4,000,000; by a “complete” set being understood a set in which all of the meteorological elements
given in the above series appear.
Under (c) are comprised the Forms 105a and 105b, containing all of the meteorological data
returned to the Office since January 1, 1888, the date of the adoption by the Office of the syn-
chronous system of observations, demanding of the observer but a single observation per day, that
to be taken at the same absolute moment of time, viz, Greenwich Mean Noon, by all observers, no
matter in what portion of the earth each one might happen to be situated.
The development of the idea of simultaneous observations of wind, pressure, and temperature
over the entire globe is of such interest that it may with propriety be briefly reviewed.
The proposition in its first shape, came probably from Buys Ballot, director of the Royal
Netherlands Meteorological Institute at Utrecht, and later from Admiral Fitzroy. Demanding,
as it did, international cooperation, it took tangible shape under Leverrier, who, in 1861, proposed
that the globe should be divided for the purpose of weather study; France to take the Atlantic
Ocean, England to take the Indian, while Russia and the United States should take Asia, the
Pacific Ocean, and America. -
As a result of Leverrier's proposal, daily synoptic charts of the Atlantic north of the parallel
of 40° N., were published for nine months of 1864 and the whole of 1865. The full realization of
the scheme was never attained, owing to lack of sufficient observations over the oceans other than
the North Atlantic.
In September, 1873, Captain Hoffmeyer, of the Danish Meteorologic Institute, began the issue
of daily synoptic charts of the North Atlantic and the adjacent continents. The publication of
these charts was kept up until November, 1876, when it was suspended owing to lack of means,
having been maintained thus long largely by the personal exertions of Captain Hoffmeyer. The
need of such charts was, however, so urgent in marine meteorology that the project was not allowed
to perish, and in December, 1884, by virtue of an agreement between the Danish Meteorologic
Institute and the Deutsche Seewarte of Hamburg, the publication was resumed, and has since
been kept up, the charts at the present time being four years in arrears.
The international publications of the United States Signal Service began with the issue of the
Daily Bulletin of Simultaneous Observations, July 1, 1875. This publication was continued until
June 30, 1884. Daily international charts were published from July 1, 1878, to June 30, 1884, and
from October 1, 1886, to December 31, 1887. A tabulated summary of international observations
was published from January, 1888, to June, 1889, after which the international work of the United
States Weather Service was formally discontinued.
The United States Hydrographic Office began its work of simultaneous meteorological obser-
vations with the issuance to its observers of the old Forms 105, dating from January 1, 1888. The
general character and compact style of this form, a single leaf sufficing for the observations of a
whole month, the simplicity of the observations required, and the brief but explicit instructions
as to the method of taking them, seemed to commend itself to seafaring people, and masters of
vessels readily undertook to keep the log. In 1888, the year of the issue of the Form 105, abstract
meteorological logs were returned by 46 Government vessels and by 544 vessels of the merchant
marine. At the opening of the year 1897, 2,039 voluntary observers were recorded as regularly
cooperating with the Office in its meteorological work. An analysis of this number shows 90
Government vessels of various nationalities, 29 land stations, and 1,920 vessels of the merchant
marine, distributed among the various nations of the earth as follows:
British. ... ---------------- 1, 136 Belgian ----------...-------- 21 Hawaiian.................... 5
American -----...--------- 366 || Spanish------------........ is j apanese--------- - - - - - - - - - - - - 3
German...... ------------ 159 Danish. . . . . . . . . . . . . . . . . . . . . 14 Australian ................... 2
Norwegian -------------. . 80 Chilean ... . . . . . . . . . . . . . . . . . 8 || Nicaraguan .................. 2
Dutch ------------------. 42 Russian. ------------------- 7 || Mexican -----------------.... 1
French------------------. 24 || Portuguese.---------------. 5 Bolivian ..................... 1
Italian................... 21 Swedish . . . . . . . ... --...----. 5.
As stated above, the form called for a single set of observations per day, to be taken at the
hour of Greenwich Mean Noon; and for the convenience of observers, tables were published giving
to the nearest four minutes (one degree of longitude) the local time along each meridian corre.
sponding to the hour of noon at Greenwich. As a check upon the hour of observation, a column


7
*
is set apart for entering the local time, as given by the ship's clock. A complete set of observa.
tions requires the space of a single line, the various items being entered in columns, the headings
of these being as follows:
Time of observation: Temperature—Continued.
1. Day of month. 10. Air, wet bulb.
2. Ship's time. 11. Water at surface.
Port or position: Weather:
3. Latitude. 12. State of, by symbols.
4. Longitude. Clouds:
Wind: 13. Form of, by symbols.
5. True direction. 14. True direction from which moving, lower.
6. Force, 0–12. 15. True direction from which moving, upper.
Barometer: 16. Amount, scale 0 to 10.
7. As read off. Sea:
8. Attached thermometer. 17. State of, by symbols.
Temperature: 18. True direction from which coming.
9. Air, dry bulb. Remarks.
The present form of the abstract log, an oblong booklet 83 by 34 inches, containing either 16
or 32 pages, each page furnishing space for the record of a single day's observations, was adopted
January 1, 1895, as one that answered better the needs and convenience of the observers. A
specimen of the latter, completely filled out from an actual log, is given below:
Form 105. Greenwich Mean Noon Report.
Date, August 6, 1896.
WEATHER REPORT FOR GREENWICH MEAN NOON FOR ONE DAY.
Estimated current for 24-hours,

TIME or observatio N. Port or position. | wind. BAROMETER.
Knots...... 1+----------- per hour.
----------------- - Longitude. Thue Force. As Read Att.
Ship's Time. * ºn.) | Dmºon. 'º. or'F. Then. -
Setting ------ ENE--------.
o o º Inches. o
2h. 10m. a.m. ----------------- 5 09 N. 149 06 W. SSE. 4. 30.00 81
WEATHER experienced For
TEMPERATURE. WEATHER. CLouds. SEA. PAST 24 Hours.
AIR, Anh, WATER I State of, I Forms of AMount, I state of true diºc. Lºh-ºººººººººººººº...?"
tº wºº ºr sº lºsº | º' Mºº scale" | my syM.' ºrios rºom º sea moderate; clear
Bulb. bulb. FACE. BOLs. bols. 0 to 10. pois. which coming. W*.
- º o
s' 79 82 c. S Cu. SSE. 9. M. SE.
Kind of Barometer? Aneroid 2 or Mercurial?...... Mercurial----------------------------------------------
Barometer------ 0.06 inch.................. too high;------------------------------------------------ too low.
When last compared?------ July 8, 1896 ---------------. Where?------ San Francisco ------------------------
Kind of thermometer? Fahrenheit, Centigrade, or Reaumur?...... Fahrenheit ---------------------------.
Note.-Information regarding instruments to be given once for each book. (Continue remarks on back if necessary.)
The matter of the new form is almost identical with that of the old, the only changes made
being the omission of the direction of motion of the upper clouds and the addition of a space for
the record of the current during the preceding twenty-four hours. Greater space is also allowed
for remarks as to the character of the weather during the preceding twenty-four hours.
THE METHOD OF DISCUSSION.
At the inception of his administration in 1893, the amount of meteorological data comprised
within the forms just described in the Office awaiting discussion had accumulated to such an extent.
and was still accumulating, that the present Hydrographer felt that the most urgent and the most
important matter calling for his attention was its disposition and treatment, the latter necessarily
to be of such nature that the full value of the countless observations might be realized in a manner
such that not only the conclusions deduced from their discussion might be put in such a form as to
become a practical benefit to the navigators by whom they were taken, but also that the theoretical
meteorologist might have therein a readily accessible store of observations upon which to base his
future researches into the mechanics of the atmosphere.

8
The study of meteorological observations may follow either one of two methods:
In the first place, they may be regarded as purely climatological data, from which there may
be deduced, after the lapse of sufficient time, mean values of the elements concerned, holding good
for certain limited squares or areas, and if computed for the proper epoch, sufficient to make
evident the cyclical variations of the special element under consideration.
In the second place, they may be considered as observed values of a function of several
variables, the general law of whose variation is to be derived from a consideration of these special
observed values. The advantage of the second method is that, having once determined the law
in question, we are enabled to employ it for purposes of prediction.
It was the desire of the Hydrographer that the meteorological records contained in the Hydro-
graphic Office should be put into such shape as to lend themselves readily to treatment by either of
the methods. To follow the first method exclusively would be to disregard what is admitted to
be one of the most valuable features of the daily observations of the past nine years, viz, the
fact that they are simultaneous, and that with their aid it is possible to construct a synoptic
weather chart covering the navigable portion of the globe. Such, in fact, was the aim of the orig-
inal designers of the system, and such is the use to which the observations, as they are received
from day to day by the Office, are at present put, daily meteorologic synoptic charts of both the
North Atlantic and the North Pacific being constructed, which serve as the basis of the monthly
Pilot Charts of those oceans. The value again of such synoptic charts is strikingly exemplified
in a recent noteworthy publication of Professors Van Bebber and Köppen upon the “Isobaric
Types of the North Atlantic,” in which it is shown that the apparently haphazard and fortuitous
distribution of atmospheric pressure over the North Atlantic is capable of being reduced to a small
number of individual types, each with its attendant weather conditions, each showing a certain
persistency and a certain tendency to transform itself to other types. On the other hand, the
climatological side of the question can in no sense be omitted. In spite of the strenuous exertions
of the several marine meteorological institutions of Europe, and the earnest recommendations of
repeated maritime conferences, the mean values of the various meteorological elements, upon which
we must depend for our knowledge of the general circulation of the atmosphere, are all but unknown
over those regions of the ocean lying outside of the main channels of commerce, owing to the
lack of sufficient observations. Even in the center of the North Atlantic, within, for example, the
five-degree square inclosed between the parallel of 25° and 30°, and the meridians of 55° W. and
60° W., the Deutsche Seewarte, in its exhaustive publication, “IResultate der Meteorologischen
Beobachtungen von deutschen und holländischen Schiffen,” was able to muster for the month of
June, from which to deduce the mean value for that month, but 53 readings of the barometer, hav-
ing a range of five-tenths of an inch, and extending over a period of thirteen years. Other squares
and months were almost equally barren. Under such conditions, it is evident that the climatology
of the North Atlantic, leaving out of consideration the other and less frequented oceans, is far
from complete.
It was the aim of the Hydrographer to devise a system of filing the observations such that
they might be readily utilized in both of these ways: First, for the construction of synoptic charts
of the whole or of any portion of the navigable globe; second, that they might be readily
accessible for the discussion of the climatological features or the average meteorological
conditions of any specified square, zone, or area. Such a system needs to be elastic, to readily
admit of additions and the incorporation of new matter, to be uniform, to be free from errors of
transcription and filing, and to occupy as little space as is consistent with clearness. The
necessity of assembling the observations of each day, and the fact that the period during which
the observations for any one day are returned to the Office may extend over several months,
made it desirable that each set of observations be independent. It was therefore decided that
in the transcription a separate sheet or card should be allotted to each daily set of observations.
Since, moreover, the purpose in view was twofold—the first, the construction of synoptic charts,
demanding that the observations be filed according to date; the second, the study of the
climatology of the sea, demanding that they be filed according to position—the system of
transcription adopted must, if possible, be such as to admit of the work being performed
in duplicate.

THE APPLICATION OF THE HOLLERITH SYSTEM OF TABULATION.
After due deliberation and the consideration of various plans of transcription, it seemed to
the Hydrographer that the Hollerith system of electrical tabulation enjoyed these essential
conditions to a higher degree than any other method yet presented.
As is well known, this system was employed in tabulating the returns of the Eleventh
United States Census. It has the disadvantage of being symbolic in character, the information,
º -
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s
Fig. 1.-Keyboard Punch.
after recording, being represented by the position of certain holes punched in a light card by a
die. Its great advantages are that the work could be done at one stroke in duplicate, and that
the information contained upon any number of cards, however large, is capable of being rapidly
tabulated and averaged by the machines devised by the inventor for that purpose. The process
of recording and that of tabulating are quite distinct. The fundamental idea of the first is to
punch holes in cards so that the positions of these holes will correspond to certain data, and of
the second to pass these cards through presses, by which the perforations in the cards are made
** she ºne vre inne ºne
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Fig. 2.-System of Holes in Keyboard Punch, with Fields and subfields.
* Moe se lºs
to control the operation of electro-magnets, which in turn act upon counting or integrating
mechanisms.
The actual punching of the cards is done by the machine shown in fig. 1, known as the
“Keyboard Punch.” It is about the size of a typewriter tray, having in front a perforated punch
board of celluloid, shown, as arranged for recording the meteorological data of the Hydrographic
Office, in fig. 2.
Over this keyboard, and nearly flush with its surface, swings freely a sharp index finger,
whose movement, after the manner of a pantagraph, is repeated at the rear by a punch. The






























10
movement of this punch is limited between two guides, upon which is placed the card, 63 inches
long by 34 inches wide, which, after punching, is to serve as the symbolic representative of each set
of observations.
The card devised for use in the Hydrographic Office is shown in fig. 3. This card has been
-
punched to record the set of Greenwich mean noon observations given on page 7. For the sake
-O 19 || 0 re 0 20 40 60 || NR Sh I NR Wr I NR INRI NR 0 20 40 60 || NR ne|N
5 10 15|Q
- 0 20 20 pm s || 0 Q 10 15 N O || 0 5 An 27 || 0 C; I St I St 0
- 40 60 || 0 0 1 2 3 4 || S W 10 || 0 |Q|28 || 0 Q 2 3 4 |Cisſ N | N
- 0 le 0 E | 0 20 40 60 || 0 | | | 2 || 31 O | NR 20 40 O 80 Cicº C | E 2
|- s 10 || 10 || 5 80 100 120 Op. 2 3 || 3 O o laoſ o 5 to © Ac As S 3
20 40 60 Olo 1 2 3 ele, w w| 4
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7
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= 0 O || 2 || 2 B e O 40 ſo © | 0 | N St. NR 0 1 O 3 + · S | 4 || 4 || 7
... 10 || 0 || 3 || 3 F | 2 | 60 80 || 2 | E | 2 |Q| R H B | NR b Q d f |O || 6 || 8
a 2 || 4 || 4 3 || 0 5 || 4 || S e S | S L c | g h 1 m o p q |Q
© 4 S 4 || 10 C. C. W I 6 || W L T O G Tº r s tº u w z | 10
ol zol a sal 'ºl | | | | asl l l l l l l l l l
-O 19 || 0 ||am 0 20 40 60 NR Sh NR Wr NRI NRI NR 0 20 40 60 | NR NFle NR
- 0 20 |20 pm S | 0 Q 10 15 N O || 0 5 |An 27 || 0 5 10 15 O |ci | St | St | 0
- 40 60 || 0 0 1 2 3 4 || S W 10 || 0 O 28 || 0 O 2 3 4 || Cis N N | 1
reſºle 9 | E | 0 20 40 60 || 0 || || 2 || 31 Q |NR 20 40 O 80 cicule E I 2
- 5 10 || 10 || 5 O 80 100 120 Op. 2 3 || 3 O || 0 || 30 || 0 5 10 O | AC As S | S 3
ke|9|| 0 O 10 15 |160] + 5 20 40 60 O || 0 1 2 3 Q |Q|w w| 4
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Fig. 3.-Hydrographic office Card for Recording Marine Meteorological observations.
of clearness, both “date” and “position” cards are shown, the difference between them being
explained in a later paragraph.
The punch moves over the surface of this card in exact correspondence with the movement of
the index finger over the surface of the keyboard, and the depression of the latter at any hole of
the keyboard serves also to perforate the card at a corresponding point.
:

11
It will be noted that the keyboard (fig. 2) has in all 264 holes, arranged in 12 rows of 22 holes
each, and that each hole is marked with its distinctive lettering or number. The card (fig. 3) carries
space for punching 288 holes, arranged in 12 rows of 24 holes each. The holes, when punched, are
five thirty-seconds of an inch in diameter, and the distance from center to center is one fourth of an
inch. Omitting the first two columns, of which mention will be made later, each space upon the
card has the same signification as the corresponding hole in the keyboard. Heavy lines serve
furthermore to divide the surface of both keyboard and card into groups, or fields; and light lines
divide these again into subfields. Each of these fields corresponds to some class of information
contained in each day's observations.
The present card and keyboard have been arranged with a view of recording not only the
simultaneous observations returned to the Office upon Form 105, but also the observations
contained in the old quarterly log books issued to observers, and indeed meteorological information
in any shape. Inasmuch, however, as the Form 105 is the most comprehensive, and likewise that
most frequently employed, the description given will refer more specifically to that form.
In order to bring the information, with its multitude of variations, contained upon Form 105
within the compass of the card, it was necessary to employ some system of abbreviation in
expressing numerical quantities. The system adopted marks, first, the nearest 20; second, the
nearest 5; third, the nearest unit. Thus, 26=20+5+1; 78–60+15+3; 152=140+10+2. This,
of course, applies only to the variable parts of those quantities. Furthermore, where the report
fails to give any information called for, the same is denoted by the symbol “N. R.” (not recorded),
the subsequent tabulation requiring that some symbol appear in each field.
Leaving out of consideration for the present the explanation of the fact that fields 1 and 2
appear upon the card and not upon the keyboard, the meaning attaching to the several fields is as
follows:
Fields 1, 2, 3, and 4 correspond to year, month, day, and hour, respectively. (The months are
to be recorded numerically, January=1, February=2, etc., using the abbreviated notation.)
Field 5 gives the latitude to the nearest degree, from 0° to 799, inclusive.
Field 6 gives the longitude to the nearest degree.
Field 7 gives the direction of the wind to the nearest compass point. The first subfield gives
the four cardinal points; the second, the number of compass points to the right of the cardinal
point. Thus, NNE.-N.--2; SW.-S.--4; WNW.-W.--2, etc.
Field 8 gives the force of the wind on the Beaufort scale. (“Vr.” denotes variable.)
Field 9 specifies the barometer, whether aneroid or mercurial.
Field 10 gives the barometric reading to the nearest hundredth of an inch, corrected, if the
barometer is mercurial, for initial error, temperature, and height above sea level; if aneroid, for
initial error and for height above sea level.
Fields 11, 12, and 13 give respectively the reading (Fahrenheit) of the dry-bulb thermometer,
of the wet bulb thermometer, and the temperature of the surface water.
Field 14 gives the weather, according to the Beaufort system of symbols. (v = visibility of
distant objects is omitted.)
Field 15 gives the form of clouds, according to the international system of cloud classification.
Fields 16 and 17 give the direction to the nearest two compass points from which the clouds,
lower and upper strata, are moving. The meaning of the subfields are the same as in the case of
the wind.
Field 18 gives the amount of cloud on a scale of 0 to 10. (0 = cloudless; 10 = sky overcast.)
Field 19 gives the character of the sea, according to the Beaufort notation; field 20, the
direction from which it comes to the nearest two compass points.
Field 21 gives the direction of the current observed to within two compass points; field 22,
its velocity per day to the nearest mile.
Field 23 records the observation of ice, and its character. (B =bergs; F = field ice.)
Field 24 records the observation of waterspouts.
Fields 1 and 2, recording the year and the month, respectively, will evidently be constant for
the 10,000 or more reports received during any one month. A saving in time and freedom from
error may therefore be attained by punching these two fields for the whole number of reports


12
simultaneously as far as possible. This is effected by means of the Gang Punch shown in fig. 4.
In this punch the several pins are capable of being adjusted to punch any possible combination
of year and month from the beginning of the eighteenth up to the close of the twentieth century,
the period covered by the card, and as many cards as are desired may be punched at a single
operation.
Upon a card thus arranged it is practicable to record every probable modification of the several
meteorological elements ordinarily observed at sea, along with the various physical phenomena
with which navigation is closely connected. The records thus obtained are absolutely uniform
in size and shape, and much less liable to error than if transcribed in manuscript; are readily
translated by means of a reading board into the originals, and are so compact that the space
required for filing is reduced to its lowest terms. The main advantage, however, the ease with
which, by the aid of machinery, the climatological data can be extracted from the whole mass of
observations, will be returned to later. -
To meet the demands of the system of double filing, all cards are punched in duplicate at a
single operation, one set being filed as “date cards,” the other as “position cards.” The body of
the two cards is precisely identical, the only difference being in the signification attached to the
marginal ruling, the explanation of which will be given later. As a guard against improper filing,
such, for instance, as both cards finding their way into one case, date cards have the upper
right-hand corner clipped; position cards, the lower right-hand corner. A card of either sort
accidentally finding its way into a bundle of the contrary sort will have that corner projecting,
and may thus be detected and removed.
Fig. 4.—Gang Punch.
After punching, the cards are placed in drawers provided for holding them, each drawer
consisting of three compartments, each compartment accommodating 3,000 cards. The date
cards, filed chronologically, occupy one case, all the cards for any one day falling together, guide
ºards separating successive days. In a separate, but precisely similar case, the position cards are
filed according to the five-degree latitude and longitude square to which they belong, the order
of succession of the squares in the filing cases being the order in which they occur as we go from
the equator, taking each five degrees of longitude, beginning with the meridian of Greenwich, in
succession. The quadrants of the earth are kept distinct, the northeast quadrant coming first,
the southeast, the southwest, and the northwest following in the given order. Guide cards,
marked with the limiting parallels and meridians, separate the several squares from each other,
and secondary guide cards subdivide the observations of each square into monthly groups.
For the purpose of broadly distinguishing the locality to which any observation belongs, the
plan was adopted of designating by the color of the card the quadrant of the earth in which the
recorded observation was taken, the earth being divided for this purpose into four quadrants, with
the equator and the meridian of Greenwich as dividing lines. Pink was selected as the color
of the northeast quadrant, blue for the southeast, green for the southwest, and white for the
northwest, the quadrant in which observations are by far the most numerous. These colors
apply to both date and position cards.
A result of this subdivision is that no one of the great oceans is covered by cards of one
color. But while a meridian might have been selected which would more nearly accomplish this,
for example, 110° E., yet the advantage thus gained would probably have been outweighed by the
resulting confusion of longitudes.
.

13
ERRORS IN PUNCHING.
There seems to be no practical systematic method, except duplication by different operators, of
discovering errors made in punching the cards. According to the account of the use of the
Hollerith Keyboard by the Census Bureau, the only class of errors considered were what is known
as “inconsistent errors,” e.g., the recording of a child of 10 years of age as of no sex. These
would inevitably be detected by the tabulating machines. With regard to other errors, the rather
doubtful claim is made that “it is at least as easy to punch the right hole as it is to punch the
wrong one.”
In spite of this, however, the slight probability of committing an error, the almost automatic
simplicity of the work, and the constantly increasing skill of the operator, assisted by careful
scrutiny of the cards, and the intervention of such partial mechanical checks as experience alone
can devise, will, it is thought, be sufficient to render negligible the effect of errors thus introduced.
In case of the discovery of an error, or if for any other reason it becomes necessary to refer to
the original abstract log, the number borne by each vessei upon the official list of vessels observing
for the Hydrographic Office, stamped upon the back of both date and position card, serves as a
means of identification. -
ERRORS IN FILING.
Date cards.-The error most likely to occur in filing these cards is that a card of one date may
be accidentally mixed with those of another date. The following mechanical device will reveal
such an error.
Along the bottom and left-hand side of the card short marginal lines are printed, extending
inward from the edge. Those along the side to which meaning is attached, eight in number, are
sufficient to indicate the month, using the same abbreviated system of notation employed in the
body of the card. The first eleven of those along the bottom are used to indicate the day of the
month, the twelfth, marked “G. N.,” standing for Greenwich Noon. These lines are equidistant,
being one-fourth inch apart, and are symmetrically placed with respect to the left-hand lower
corner of the card. Each line is properly designated.
Before placing the cards upon the keyboard punch, the marginal lines corresponding to the
month and day of the observation are punched, using for this purpose a conductor's punch, the
width of which, one-half inch, is just double the space intervening between successive lines, and
whose jaws carry a light shoulder, limiting the admission of the card to the proper distance.
Accurate placing and depth of the punch mark are thus insured, the indentations made being
three thirty-seconds of an inch in width and extending one-eighth inch inward from the bottom
of the card.
Having completed the process of punching the body of the card, the date as shown by the
marginal indentations and the date as shown in the body of the card are compared to make
sure that the two agree.
The bundle of cards under consideration is now placed upon the templet shown in fig. 5, of
a size corresponding to the bottom of the card, and having channels placed at distances corre.
sponding to the marginal lines of the card. These channels carry adjustable guide bars of such
size as to readily fit into the marginal indentations. The bars for any desired month having
been put in place, June, for example, the sixth month, calling for bars in spaces marked 5 and 1,
December in spaces 10 and 2, etc., the cards, resting on the templet on their left-hand edge, are
gently shuffled until those indented for that month have fallen astride the guide bars, while any
one not so indented will project, and may thus be withdrawn.
Setting the guide bars for any particular day, the same process will separate out from the
remaining cards all excepting such as belong to that particular day. The same templet answers
for both purposes. Furthermore, by placing an additional guide bar in the channel marked
“G. N.” the separation of observations taken at hours other than Greenwich noon, should any
such exist, from those taken at that hour is readily accomplished.
Position cards.-The position cards are filed in monthly groups, according to the five-degree
square within which the observation is taken. The error most likely to occur in filing the position

14
cards, therefore, is that a card belonging to a certain square become mixed with those belonging
to another square.
The method employed to detect such an error in the date cards is equally applicable here.
Along the bottom and left-hand edge of the position card similar marginal lines are drawn, those
along the bottom sufficing to mark the longitude, those along the side to mark the latitude, in each
case the value indicated being the inferior five degrees of the square. The same abbreviated
notation is employed as in the body of the card. In distance from each other, and from the lower
left-hand corner, these marginal lines are identical with those on the date card, in order that the
same templet may be employed. The marginal lines corresponding to the square of observation
are punched, using the same conductor's punch as in the previous case, before the body of the card
is touched, and a comparison afterwards made to see that the position as given to the nearest
degree in the body of the card falls within the square given by the marginal indentations. The
same process by which, with the assistance of the templet, the cards for any one day and date
were separated from a bundle of date cards will now serve to separate out the cards belonging to
any one square from a bundle of position cards, and by the same device the Greenwich noon
reports for any square may be separated from those taken at other hours.
A test of the proper grouping as to month is at once obtained by endeavoring to pass a prob-
ſ
º ººz
ºf fe Tſii
- |
º **
T º | fº
= Liſt
Fig. 5–Separating Templet.
ing wire through the punched holes indicating the month in question. A single card wrongly
filed will serve to check the further entrance of the wire.
From the date cards, thus arranged, it is possible to construct a synoptic chart of the whole
or of any part of the ocean, provided, of course, that the observations are sufficiently numerous.
From the position cards, the average values of the various meteorological elements can be
obtained not only for the five-degree squares, but also, and with equal facility, for each one-degree
square; and not only for each month, but also, if necessary, for any particular portion of a month,
or for any day, or for any hour, all of this work being performed automatically by the separating
and counting machine.
This machine, shown complete in fig. 6, consists of three parts—the press, or circuit-closing
device, the dials or counters, and the sorting boxes. The press is shown in perspective in fig. 7
and in detail in fig. 8. It consists of a hard-rubber plate, provided with 288 holes, the relative
positions of which correspond with those of the holes in the keyboard and gang punches. Each of
these pockets is partially filled with mercury; and they are thus in electrical connection with the
binding posts and switchboard at the back of the machine. Above the hard rubber plate swings a
reciprocating pin box, which is provided with a number of projecting spring-actuated points, so hung
as to drop exactly into the center of the little mercury cups below. These pins are so connected
that when a punched card is laid on the rubber plate against the guides or stops, and the box is
brought down, all the pins that are stopped by the unpunched surface will be pressed back, while
those that correspond with punched spaces pass through, close the circuit, and count on the dials.

15
º
º
º
-º
-
-
- …
- ºr
|-
ill lº
Fig. 6.-General View of Tabulating System.
|
---
|
T- -
Fig. 7-Circuit-Closing Press.









16
-
The dials are shown in detail in figs. 9 and 10, and may also be seen grouped in position in
fig. 6.
Each dial is divided into 100 parts, and two hands travel over the face, one counting units
and the other hundreds. The train of clockwork is operated electrically, by means of the electro-
magnet, whose armature, as it moves each time the circuit is closed, carries the unit hand forward
º- -
-
- Wºź
º
@
%
Fig. 8-Detail of Circuit-Closing Press.
one division, while every complete revolution actuates a carrying device, which in turn causes the
hundred hand to count. The electrical connections are made simply by slipping them into the
frame and clips shown in the upper part of fig. 7.
The third element in the system is the sorting box, shown in fig. 11 in perspective, while
fig. 12 is a diagram of its mechanism.
-
-
-
--- | - -- º -
* > * - -
** ſill/I'll]].
vir
**uctuºunteer
arºuºurºurt
lºtu, º, Counter. Fig. it).-Counter.
The box is divided into numerous compartments, each of which is kept closed by a lid. As
seen in fig. 12, the lid L is closed against the tension of the spring S by the catch a at the free end
of the armature 4. If the circuit is closed by the press on the machine, through the electro-magnet
E, the armature A is pulled down, releasing the trigger of the lid L, which is at once thrown up
by the spring S, and remains open until closed by a touch of the operator's hand. The connections
with the machine are made by means of the short cable seen at the left of the sorting box.













17
If, now, it is desired to make the familiar tabulation of the number of winds in a given square
blowing from each direction, the binding posts of the switchboard corresponding to these terms
are connected with the binding posts of the dials on which these items are to be counted. If it
is also desired to assort these cards into groups according to the force of the wind, the binding
posts of the switchboard representing such groups are connected with the clips into which the
sorting box plug fits. The circuit being thus prepared, when a card is placed in position in the
press and the handle of the pin box is brought down by the operator, so that the circuit is closed
through each hole in the card, not only will the registration be effected upon the dials, but the
sorting box that has been selected for a given group is opened, all the other sorting boxes remain-
ing closed.
It is, however, in tabulating combinations of phenomena that the machine exhibits its special
adaptability to the work in hand. Let, for instance, the problem be to determine the occurrence
of winds exceeding a certain limit of force, under given conditions of direction, barometer, and
Fig.11.-Sorting Box. Fig. 12.-Detail of Sorting Box and Circuit.
temperature. Such tabulation is effected by means of relays, controlling the action of the regis-
tering dials. These relays are mounted together in racks, at the bottom of the case shown in fig. 6.
In the case just suggested, the wind forces exceeding the given limit are joined up in multiple
arc, and the wire is then brought to one contact of the relay corresponding to the direction. From
the other contact it is carried to the relay corresponding to the given barometer, and thence to a
third relay corresponding to the temperature. The counter will therefore be operated only when a
card punched for the given combination is inserted in the press. Each of the relays, by joining up
in multiple arc, may be made to cover a given range of value, and an analysis of any degree of
fineness may thus be obtained. Furthermore, the machine tabulates in one list the cards satisfying
the required conditions, and in a separate list the cards not satisfying them, including them under
the general heading of “all others.” This is done for every operation through which the cards are
put, thus giving a constant check as to whether any cards have been missed, counted twice, or
have otherwise failed to register, the check being effected by joining up in multiple arc all of the
holes in each field except those called for by the conditions.
15361—2


18
The integrating device, by means of which average values of numerical quantities are obtained,
consists in a cylinder around whose circumference studs are set; spring contact points connected
to the mercury cups of the press; a motor for revolving the cylinder in conjunction with a train of
ordinary registering mechanism; and a device for starting the motor so that the cylinder will make
one revolution. A card being put in the press, the circuit is closed through a given counter to the
battery, to the cylinder of the integrating device from one of the nine contact strips of the
integrator, through the corresponding mercury cups uncovered by the punched hole of the card,
through the plunger of the pin box corresponding to that hole, and back to the counter. At the
same time another circuit is closed through the magnet when the handle is brought down, which
allows the train to revolve the cylinder of the integrating device one revolution. During that
revolution the circuit through the dial counter will be made and broken from one to nine times,
according to the contact strip which is brought into operation. Any number of counters can thus
be operated at the same time, they being connected in multiple arc.
With the assistance of the tabulating machinery just described and in the hope that it will to
some extent be an efficient substitute for the working force, of which it has long stood in need, the
Hydrographic Office has undertaken the treatment of the meteorological material which the recent
years have served to accumulate. In its work in the past the Office has been made the subject at
times of inconsiderate criticism, having its foundation rather in the ignorance on the part of its
critics as to the conditions under which the Office exists than in any lack of merit in its publica-
tions. The present Hydrographic Office, established by act of Congress in 1867, is in no sense the
successor of the Office represented by Lieutenant Maury at the Brussels Conference in 1853, and
has no legislative authority to prosecute the work which was discussed there, even if it were
regarded as desirable to pursue that method of investigation at the present day.
By acts of Congress the Hydrographic Office is authorized, in addition to its other and more
specific duties, to prepare the monthly pilot charts of the North Atlantic and North Pacific oceans.
Through the issue of these charts it has opened for itself avenues for obtaining meteorological
observations direct from mariners of the world upon a scale which promises to become sufficiently
extensive to enable it to circumvent the obstacles which meteorological conferences have labored
to overcome.
At the time of the establishment of the British Board of Trade Meteorological Office, for the
purpose of carrying on the work proposed by the conference at Brussels, the wind was the princi-
pal motor of commerce, and the deductions of the averages from the logs of many vessels which
go to make up the results in climatology was of paramount importance. Since then circumstances
have undergone radical changes. Commerce now follows certain well-defined tracks, and it is
difficult to understand how in future the system of averages can be carried on over the broad field
formerly visited. At the present day, instead of proceeding solely with the deduction of averages,
it is a question whether greater advances in knowledge can not be ultimately made and benefits
gained for commerce and navigation by following the method sketched on an earlier page, viz, by
the construction of daily synoptic charts of the two hemispheres. Such charts are now prepared
in the Hydrographic Office. Their publication, however, owing to lack of means and inadequate
force, is at present not contemplated.
All of the adverse criticism aimed at the Pilot Chart comes from men having a scientific specialty,
namely, meteorology, but who have no practical knowledge of the sea. Taking the chart out of its
proper domain, they insist upon judging it as a work of meteorological investigation, whereas it is a
chart whose very foundation is utility. It is declared to be ephemeral; yet much of theinformation
printed upon it results from averages and is carried upon successive charts from year to year; and
in estimating the value of the ephemeral matter, it should be remembered, as nautical men know,
that even the smallest hint of information, or even negative information, saves ships and lives.
Independently of the Pilot Chart, the Office has had neither the authority nor the means of
pursuing the work of scientific investigation. The amount of meteorological material on hand has,
however, now reached such dimensions, owing to the rapid increase in the number of its voluntary
observers, many of whom have, in this respect, given the same allegiance to the Hydrographic
Office as to their own national institutions, that the discussion of this material is now demanded,
if only as a return for the confidence displayed by these observers, in the promise that their labors
would be for the ultimate benefit of navigation. A step in advance has now been taken in this
direction which it is hoped will prove effectual.

:
NOTE ON BAROMETER COMPARISONS.
In its every day use, the ordinary ship's barometer is a purely differential instrument, looked
upon by the mariner as a monitor, the direction and extent of whose fluctuations serve to warn
him of approaching atmospheric disturbances. Of its use as an absolute measure of the elastic
pressure of the atmosphere, most mariners know nothing. His barometer may and often does
indicate pressure differing by several tenths of an inch from the truth, and yet answer his purpose
completely. So utter was the lack of knowledge of the barometer's true function that the following
paragraph finds place in the Report of the Maritime Conference at Brussels:
“That an instrument so rude and so abundant in error as is the marine barometer generally in use should, in this
age of invention and improvement, be found on board any ship will doubtless be regarded hereafter with surprise,
and it will be wondered how an instrument so important to meteorology and so useful to navigation should be
permitted to remain so defective that meteorologists, in their investigations concerning the laws of atmospheric
pressure, are compelled in great measure to omit all reference to the observations which have been taken with them
at sea.”
Although, owing to improved construction and greater knowledge, barometric observations
at sea are to-day worthy of confidence to a far higher degree than at the time when this was
written, the ship's barometer still leaves much to be desired in the way of accuracy, and of late
years the tendency has been, owing to the multiplicity of errors to which it is subject and the
apparent impossibility of eliminating them, to intrust the accurate determination of the atmos.
pheric pressure to carefully constructed and observed barometers ashore, with which the various
ships' barometers are from time to time compared and the error of their reading determined, this
error remaining fairly constant over short periods. -
The method of making these comparisons at present employed in the Hydrographic Office is
most complete in detail. Branch Hydrographic Offices, each equipped with a standard barometer,
which is read at hourly intervals during the day, are now established along the Atlantic Coast at
Boston, New York, Philadelphia, Baltimore, Norfolk, Savannah, and New Orleans, and along the
Pacific Coast at San Francisco, Portland, and Port Townsend. A vessel arriving at any one of
these ports returns to the Branch Office the meteorological forms which she has filled out during
the voyage, and in the letter acknowledging the receipt of these reports receives a franked postal
card of the form shown in fig. 13, requesting that the ship's barometer be carefully read by the
regular observer at a certain hour each day for several days of the vessel's stay in port, and the
reading, along with the hour of observation, be noted in a special column on the card. The
readings for comparison being made by the regular observer, are thus affected with the same
personal error as the ordinary observations. The card is then returned post free to the Branch
Office, and the corresponding readings of the standard barometer for the several specified days
and hours are added by the person in charge, these readings being copied from the barometric
records. The card is then forwarded to the Main Office, and the value of the observed correction,
with the date, is entered upon a second card designed for the purpose. All subsequent corrections
of the same barometer are similarly entered in their proper order upon the same card, space
being provided thereon sufficient for the corrections of several years. Each of these cards thus
furnishes a complete history of the behavior of the special barometer from the time of its first use
in the service of the Hydrographic Office.
Other sources of information are utilized for the purpose of obtaining barometric comparisons.
In addition to those places at which Branch Hydrographic Offices have been established, continuous


barometric records by means of self-registering apparatus are maintained by the United States
19

20
Weather Bureau at Eastport and Portland, Me.; Charleston, S. C.; Key West, Fla.; Galveston,
Tex.; and at San Diego, Cal.; Seattle, Tacoma, and Tatoosh Island, Washington. These records
are of course accessible to the Hydrographic Office for the purpose of barometric comparisons.
The Greenwich Noon Observations are now regularly taken with standard instruments at many
outlying stations and islands in both the Atlantic and the Pacific Ocean. The list of these in the
Atlantic includes St. Johns, Antigua; Las Palmas, Grand Canaries; Funchal, Madeira; Barbados,
Bermuda, St. Helena, Port au Prince, Port Castries, Ponta Delgada, and many others; and in
the Pacific, Sitka, Alaska; Honolulu, Hawaiian Islands; Apia, Samoa; and the Norfolk Islands;
land observations being difficult to obtain in the Pacific owing to the inconvenient hour. The
standard barometer at each of these stations thus furnishes a check upon the barometer of any
observing vessel calling at the station. The weather maps published by the various Governments,
BAROMETER RECORD.
WESSEL (nationality, rig, and name:)
Captain --------------------------------------------
In port of.------------------------------------------
NotE.-The readings below should be for that barometer which
is used at sea to record observations for the Hydrographic Office.
Date Time.
(Local
189 . Stand'd.)
Barometer, as Att. Leave this
read off. ther. I column blank.
-----------------------------------------------------------------
Notº-Daily readings at 8 a.m. or 8 p.m., 75th Meridian time,
are best in ports of the United States and Canada, and 8 a.m.,
local time, in other ports; but other times will answer, if more
convenient. Please mail this before you sail, whether
the columns are filled or not. No postage is required if mailed -
in any United States port.
N. B.
Fig. 13.-Barometer Comparison Card.
giving the isobars, are also employed in this connection. The official weather map of the United
States contains the result of the observations taken at 8 a.m., seventy-fifth meridian time, corre.
sponding to 1 p. m., Greenwich Mean Time. During settled weather, and when the atmosphere
is free from disturbances, the hourly change of the barometric pressure rarely amounts to more
than one or two hundredths of an inch. In such cases, then, the 8 a.m. observations ashore
furnish a comparison with the Greenwich Mean Noon observations aboard observing vessels
along the immediate coast sufficiently accurate for practical purposes. Thus an observing vessel
in the harbor of Seattle, longitude 122°8' W., will record the barometric pressure at 3 hours 52
minutes a. m., local time, the Weather Bureau observer reading his standard at 4 hours 52 minutes
a.m.; and in case of freedom from disturbances, the latter may be used to determine the error of
the former.

21
The British meteorological service publishes on its daily map the 2 p. m. Greenwich mean
time observations at coast stations, and, in lack of anything better, these observations, although
two hours distant in point of time, may be employed for the purposes of comparison. The German,
French, and Spanish weather maps furnish no observations even approximating Greenwich Mean
Noon.
On the Asiatic side of the Pacific the daily weather map published at Tokyo, Japan, gives the
barometric pressure prevailing throughout Japan at 10 p.m., Tokyo time, whereas Greenwich
Mean Noon corresponds to 9 hours 20 minutes p. m., Tokyo time, a difference of only 40 minutes.
The Japanese observations are therefore quite available for purposes of comparison. At Shanghai,
Hongkong, and at Manila and several other points in the Philippine Islands hourly records of the
barometer are kept, at Shanghai by the Fathers of the Zi-ka-wei Observatory, at Hongkong by
the Hongkong Observatory, and at Manila by the Observatory of the Company of Jesus. At
Vladivostok (lat. 43° 7' N., long. 131°54' E.); Rykovskoe (lat. 50° 47' N., long. 142° 55' E.), and at
Okhotsk (lat. 59° 21' N., long 143° 17' E.), observations are taken at 9 p.m. by the Imperial Rus:
sian Meteorological Service. The publications of these institutions are forwarded to the Hydro-
graphic Office, and the observations suffice for the purposes of determining the error of the
barometer of an observing vessel calling at any one of these ports.
The question of the incorporation of the many observations made with aneroid barometers
into what is hoped will in time become standard meteorological data has been thoroughly dis-
cussed, but as yet remains open. For this reason, a field specifying the kind of barometer
employed was introduced into the recording card, by means of which the deduction of the mean
value of the barometric pressure as given by the two instruments may be carried on separately,
if desired. The adoption of the general mean will necessitate the reduction to standard gravity,
in order to render the observations comparable.
Shall full weight be attached to observations with the aneroid, shall they be admitted with
diminished weight, or shall they be excluded altogether? The British Meteorological Council,
the Deutsche Seewarte of Hamburg, and the Danish Meteorologic Institute have adopted this last
view, and their publications concerning the climatology of the sea contain the results of observa-
tion with mercurial barometers alone.
Certain facts in this connection, however, demand serious consideration. The aneroid barometer
has become a permanent institution. It is cheap, while a good mercurial barometer is expensive;
it is convenient, while a mercurial is cumbersome; it is easily read, while to read the other requires
special training; and, worst of all for science, it answers every purpose of the navigator. With
these circumstances in its favor, meteorology can only count upon the use of the aneroid becoming
wider and wider, and should take steps to convert it from a purely differential into a more nearly
absolute instrument. This has in part been accomplished, the records of barometer comparisons
contained in the Hydrographic Office showing, with regard to aneroids, a marked superiority of
those of late years over those of early years.
The improvement in the instrument itself, and the fact that numerous comparisons with a
standard are now readily obtainable, must be given due weight before it is decided to follow the
example even of such excellent authorities as the institutions cited above, and reject all observations
made with the aneroid. Upon its return to the Hydrographic Office each log is carefully scruti-
nized in this respect, and where it is manifest that the aneroid is irregular or subject to fluctuations,
the observations are rejected and the log is so marked. With such aneroids there is no question of
the worthlessness of the observations as meteorological data. The only doubt is as to the accept-
ance or rejection of observations of aneroids which have done duty alongside of the ordinary
mercurial, and with an efficiency quite equal to that of the more highly esteemed instrument.


C